Depending on the processed material from each drill must be properly sharpened. To verify the correct angle will help a specially prepared square plate of copper or aluminium with a thickness of 1 mm.
To become operational protractor enough to cut it cut, as shown in the picture: a large cutout at an angle of 120 degrees, the other half is 60 degrees and the surviving corner of a square is 90.
Recommend to read
Motor plow
Isn’t it a striking contrast: while the fields of collective and state farms are cultivated today by powerful “Kirovets” tractors, the household plots of rural workers are still plowed the...
THE LAST WORD ACOUSTIC
And so, becoming finally the owner of a high quality amplifier (see "M-K" № 7, 8 in 1975), you'd decide: "is now the Case for small: not enough speakers only sound". Not shelving them,...